julianh

I would guess you still had the unit in "On Road" mode, so it was trying to find an auto-route using routable roads and trails between the waypoints. It will try to take you back to the nearest road, then route you along routable roads and tracks until you get near to the next waypoint. When navigating "cross country", switch it to "off road" mode, and it will just point you in the straight-line to the next waypoint. Use the topo map and your eyes (look around!) to work out the best route in this case. If you join your route half-way along, it should just detect the nearest waypoint, and pick up from there. Hope this helps!

Mapwel http://www.mapwel.biz/index.htm can automatically vectorise raster images (such as aerial photos, scanned maps, etc) for compatible Garmin units. I have used it with some success for loading Google Earth images of small areas where the detail on my topo maps is not good enough (e.g. golf courses etc - it will pick up bunkers, trees, creeks, etc quite well.) It works best where you only need one zoom level - like all raster maps, they look their best at 100% zoom, and pixellate if you zoom in too far, and become over-cluttered when you zoom out. I wouldn't bother using it for large areas, unless you are prepared to scan and automatically vectorise numerous tiles at various zoom factors. The results are very good if you have the time and patience to manually "trace" over an aerial photo or map to make proper vectorised detail maps of areas of interest, but if you want a usable map in a hurry, the auto-vectorisation is worth a look. Hope this helps!

I hope you do realise that you have just boosted the "complaint count" for the Triton by one, for anyone who cares to repeat this "experiment"! (Oops - my reply makes that two - someone better close this thread down quick, before this gets out of control!)

If you have a GPSr without barometric altimeter, and you have absolutely optimal reception conditions (clear sky view, no trees, no multi-path, etc), you MIGHT be lucky enough to get something like +/- 10 metre elevation accuracy or so. You will usually get reasonably consistent elevation differentials as you move about PROVIDED you can maintain an equally good sky view at all times. (This might be possible out in the open, but in woodland or urban areas, your chances of maintaining this sort of differential elevation accuracy would be close to zero.) That is, even if your absolute elevation is out by 20 metres or so, your GPSr can generally sense relatively small elevation changes as you move about, as long as the reception doesn't change at all. However, the elevation accuracy can change dramatically from relatively minor things, such as moving to a location which partially shields your reception from just one satellite. Bottom line - use GPS elevation as a guide only, and it would be pretty dangerous to use it to look for high spots and low spots subject to flooding, unless you are using survey grade equipment. A GPSr with auto-calibrating barometric altimeter is another story. Absolute elevation accuracy of a properly used, properly calibrated GPSr with barometric altimeter is more like +/- 5 metres all day (although this is by no means an absolute guarantee!), regardless of changing satellite reception conditions. In particular, the moment-to-moment elevation stability and sensitivity of these instruments is VASTLY superior to GPS elevation alone. You would certainly be able to differentiate between two locations that only differ by a metre or two, provided you are careful with your use (I know - I do this quite frequently - but note that I am NOT looking for survey-accuracy!) For example, make sure you go back to a location with known elevation from time to time, to make sure your altimeter hasn't drifted too much in the interim. (This approach won't work for GPSr elevation alone, because the GPS elevation accuracy varies from place to place, and from minute to minute.) If you need to get better than a metre or two elevation accuracy for such a survey, a consumer GPSr won't help you, with or without a barometric altimeter. Hope this helps!

I updated the software in my Summit HC recently, and discovered to my horror a couple of weeks later that in the process of updating, track recording had been turned off. (It was particularly annoying, because I had just done a remote site inspection, and I wanted the track-logs to geo-tag all my photos.) Lesson to all - every time you update the system software / firmware, check that ALL settings are the way you like them (including tracklogs, etc)!

Why would you want to go to all the bother and expense of testing your product before release, if you can just get your customers to test it for you? (Unless you are concerned about your reputation, customer relations, and other old-fashioned stuff like that.)

Red90, I'm not sure that is totally correct. My understanding is that "sensitivity" refers to the strength of signal which can be acquired and used. An instrument which can acquire and use a signal in a particular time and place is by definition "more sensitive" than another which cannot. What the GPSr's algorithm does with that signal if / when it has been received (i.e. use it or ignore it) is another matter. A "smart" algorithm would use all available signals to acquire a fix when necessary, but would then interrogate the "quality" of each signal, and would logically "de-rate" or even ignore a particular poor-quality signal when there are more than the bare minimum number of signals required to get a 3D fix. This task could be accomplished partly by the chip-set hardware and firmware (i.e. provided by the chip-set manufacturer), and partly by the unit's software (e.g. provided by Garmin). I have no idea whatsoever what any version of Garmin hardware / software / firmware do! Conventional GPS receivers ... acquire and track signals down to around the -160 dBW level. High Sensitivity GPS receivers ... acquire signals up to 1,000 times weaker. A good High Sensitivity GPS receiver can acquire signals down to -185 dBW, and tracking can be continued down to levels approaching -190 dBW. http://en.wikipedia.org/wiki/High_Sensitivity_GPS I don't know for sure what receiver each Garmin model has, but there are definitely some GPSrs which DO have higher sensitivity than others. My Summit HC has MUCH higher sensitivity than my old yellow eTrex, my car sat-nav (no-name Chinese import), or my Samsung phone (if higher sensitivity is indicated by time to acquire a fix, and conditions under which that fix can be maintained).

I use my old yellow eTrex as a paperweight, since its display failed!

I own a Summit HC, which replaced my old B&W Vista. (I would have bought the Vista HCx, except the price differential in Australia is MUCH higher than it is in the USA, and I was doing a deal with my local vendor to upgrade a faulty unit.) Feature-wise, the Summit HC is pretty much the same as the Vista H, with the addition of a colour screen. The Vista HCx adds expandable memory, and turn-by-turn routing. https://buy.garmin.com/shop/compare.do?cID=...areProduct=8703 Colour screen is definitely useful - maps are MUCH more legible in 256-colour than 4-grey-scale. The benefits of colour more than outweigh the slightly smaller screen / no. of pixels. Given the small price difference between the Vista H and the Summit HC, there is no way I would even look at the Vista H, unless you are getting it for a really big discount. The Vista H and the Summit HC both have 24 MB fixed memory. This is enough to get several hundred square km of mapping - enough for your local area, or an average weekend trip or similar, but not enough for a trans-continental journey. Whenever I travel, I have my laptop with me, so I just upload new maps when I move into a new region - only takes a minute or so to load a new set of up to 24 MB of maps. On models with expandable memory, you can probably fit your whole country in street maps, topo maps, marine charts, etc. Turn-by-turn auto-routing is nice if you have it (and if you but the appropriate maps - routable maps are NOT included in the base price). Personally, I use car sat-nav for my road driving, and it does a MUCH better job than any hand-held - faster to redraw, bigger / brighter screen, text-to-speech, etc. However, if you want auto-routing, you need to get one of the models with expandable memory. Hope this helps!

Projector "on" or "off"? Room lights "on" or 'off"?

Yes, but the 60 Cs doesn't have a high sensitivity receiver either - they are both "old" technology. Now, if you tried the same experiment with a 60 CSx, or an eTrex "H" series or similar, you would see some REAL improvement in sensitivity, which results in MUCH better ability to get and hold a fix in all sorts of sub-optimal conditions. In ideal conditions (open sky, free of buildings, tree cover, etc), you won't necessarily get more accuracy out of the new units (but you will probably find the new high sensitivity receivers are much quicker to get a location fix from a warm or cold start), but you will certainly see the difference as soon as you move to a location with partial shielding etc.

This is definitely NOT my experience. I have owned an old B&W Vista, and now have a Summit HC. My office has a 76 CSx. The compasses on all three are VERY reliable. I have never seen a Garmin unit which displays the erratic compass behaviour that many people report, so it makes me wonder whether it is a real behaviour, or is actually user error (such as not calibrating the compass, or not holding it level) or misunderstanding. Note that the wild compass swinging you can get when very close to your destination is actually due to GPS "drift", NOT the magnetic compass. Maybe it seems more apparent when you have the magnetic compass active - I don't know - but the root cause is that your computed GPS location is moving around from second to second due to the fundamental limitations of the GPS system, and therefore the bearing to a fixed location will swing around as you appear to be dancing about. All you need to remember is: 1) Calibrate every time you change batteries. (No big deal.) This keeps my compass accurate enough to know which way I am facing all day. 2) If I have not calibrated for a few hours, I will re-calibrate when I am about to make an accurate sighting / bearing. (Not sure if this is REALLY necessary, but better safe than sorry!) 3) Hold the unit level - just like you have to do with a conventional liquid-filled compass. Hope this helps!

When your batteries go flat (and if you didn't carry spares!) then your GPSr won't work either. If you didn't bring paper maps with you (and know how to use them) - then you are lost! With respect - I never advocated that you shouldn't have a conventional compass or paper map etc. Anyone who goes "off the beaten track" without maps, compass, water, appropriate clothing and footwear, notifying friends of their destination and ETA, etc, etc, etc, is a suicidal fool. I am just arguing that a GPSr with an in-built compass actually aids the whole off-trail navigation process - if you take the trouble to learn how to used it effectively. (And the same goes for the barometric altimeter - but that's whole different can of worms!) If your sole purpose in buying a GPSr is to track down urban geocaches with known coordinates, then you may never see any benefit in getting either the compass or the altimeter. If your activities do take you off clearly-marked trails from time to time - seriously, think about the possible benefits before dismissing the whole idea! Hope this helps!

One hint: use your compass in "Course Indicator" mode when you are using "Sight'n'Go", rather than the more common red arrow "Bearing" mode. If you are at all like me, your ability to estimate distances to distant objects (plugged golf balls, refuge huts in a blizzard, small lakes when you have emptied your last water bottle, etc ) is a bit unreliable. In "Course Indicator" mode, the important thing is to try to stay as close as possible to the original straight line of sight. That way, it doesn't matter so much if you over-estimated or under-estimated the distance to your destination, at least you will know you are walking along the right line. When an obstacle forces you to deviate from the straight line of sight, Course Indicator mode will tell you how far you need to move to get back on track. If you realise you have over-shot, you can just walk back again along the original "Sight'n'Go" course line. In "Bearing Arrow" mode, the unit will always point straight from your current location to the projected waypoint at whatever location you created it, so if obstacles make you move significantly left or right of the original line of sight, it can be very hard to get back onto the original line of sight. If your original distance estimate was way off, you may find that your GPSr is not of much help at all in finding that plugged golf ball. Hope this helps!

In a nutshell ... YES! What I don't understand is why so many people seem to think this is a BAD thing?! If you need to navigate from your current location to a visible destination point with unknown coordinates, here are your options: 1) If you have a GPSr with built-in maps, or are carrying paper maps, but have no built-in GPSr compass, and no conventional compass: (Note: I would NOT recommend this as a strategy for going hiking in "The Great Beyond", but let's face it, this is the equipment that a lot of users of this forum will carry!) You would have to estimate the location of your destination by reference to other map features, estimate the bearing and distance to the destination point, "Project" a new waypoint, and then navigate along the course to the assumed waypoint, hoping that your initial bearing was not too far off. Repeat the process each time you get to another vantage point that lets you see your destination again. 2) If you have a GPSr without a built-in compass, but you are carrying a conventional compass (MUCH smarter!), the procedure is similar, but you can get a much better estimate of the bearing for the projected waypoint. Take a sighting with your compass, make a note of the bearing, and then create a projected waypoint in your GPSr, using the compass bearing. (Don't forget to allow for magnetic variation when entering the projected bearing!) 3) If you have a GPSr with built-in compass and "Sight'n'Go" feature: Point your GPSr at your destination (holding it level, and using the sight marks etched onto the unit) to get a bearing, just like you would with a conventional compass. Use this to make a "Sight'N'Go", and then follow the course. I know which one is easiest and most reliable for me!

There's one really good reason for getting a Garmin with a compass - "Sight'n'Go". This is particularly useful when you are out in the field and need to navigate to a particular feature that you see from a vantage point, rather than a waypoint with known coordinates. (I.e. this is not a particularly useful technique for geocaching, where the coordinates of your destination are known in advance.) Take a sighting to any visible distant target point you want to navigate to (e.g. hill, building, etc), and lock in a "Sight'n'Go" route. Now you can navigate to that point even if the overland route keeps the actual destination out of your line of sight most of the way. (E.g. when you are navigating through the woods, or your route take you through deep valleys and canyons.) I find this feature to be absolutely invaluable when navigating through very hilly wooded terrain, where you just can't maintain a line of sight to your destination at all times. The other feature that I like for ALL applications (including geocaching) is that I always know which way to walk to my destination, even when standing still or moving so slowly that the GPSr doesn't register any movement. As others have said, when I get to within a few metres of my destination, I put the GPSr away, and start using my eyes, rather than worrying about any apparent wild compass swinging. I have had GPSrs with and without a magnetic compass. I will NEVER buy a GPSr for outdoors use that does not have one. (Bit U use my GPSr for a lot of applications other than geocaching.)

It's "Chalk and Cheese"! On the water or out in the desert, you might not see a a lot of difference. However, in urban areas, under trees, in canyons, etc, the difference is massive - it's as simple as full-time lock vs. intermittent lock or even no lock at all. In my opinion, Garmin and other GPSr manufacturers are doing a major dis-service in the simple fact that they still sell GPSrs which don't have a high sensitivity receiver. Given the small retail price difference, I just don't understand why they are still on the market at all. (Presumably, using up old stock, rather than still being manufactured, but all the GPSrs without a high sensitivity receiver should all be in the bargain bin.) Note for example that Garmin are offering the Legend H for the same price as the old Legend, and the Vista H for the same price as the old Vista! (Not that any of these B&W models would be my first recommendation anyway), but ... WHAT THE ... ?! https://buy.garmin.com/shop/compare.do?cID=...reProduct=30122

This is an Extremely good explanation! Thank you for taking the time to post! I know this julianh. He is spot on. Thanks TCP! (Not so long ago, I had thought we would never get to participate in a GPS forum thread where we were in agreement! ) If you're ever in Australia, drop me a line and I'll happily buy you a beer or three. (My favourite pub in Brisbane is the Belgian Beer Café; coordinates: 27° 28.238'S 153° 1.760'E. Yes, I know it's a bit sad when I have my favourite pubs stored as waypoints!)

Are you sure? I have never heard of being able to change the base map in any Garmin models. Garmin MapSource WorldMap https://buy.garmin.com/shop/shop.do?pID=662&pvID=1949 is an economical way to get "slightly better than base map" standard maps for anywhere on the planet. Hope this helps!

https://buy.garmin.com/shop/compare.do?cID=...pareProduct=310 The 60Cx has a "pseudo-compass" which points your direction of movement based on your changing GPS location - but only while you are moving. When you are stationary or moving very slowly, it can point in any direction. It does NOT have a magnetic compass. The 60CSx has a true electronic (magnetic) compass, which shows your direction even when standing still (provided you calibrate it and hold the unit level). Hope this helps!

No, they are NOT the same thing; however, EPE can be loosely taken to be the unit's estimate of the current probable accuracy and precision. (It might sound pedantic in "simple English", but if we are going to have a discussion about GPSr "accuracy", we need to be speaking a common language!) Firstly, you need to understand the difference between "accuracy" and "precision". This wikipedia article http://en.wikipedia.org/wiki/Accuracy_and_precision expresses it better than I can, but in summary: "Accuracy" means "proximity to the true value", or how close does the average instrument reading compare to the true value. (I.e. is the scatter in readings random in all directions, but averaged on the true value, or is there a general "bias" away from the true value.) "Precision" means how "consistent" and "repeatable" are the readings. (Small scatter = high repeatability = high precision.) For example, an analogue watch which keeps very good time and which is set by the owner every morning at 8:00 am would be both "accurate" and "precise" (for normal consumer purposes anyway, but maybe not to an atomic physicist!) If you neglect to reset it regularly, it will gradually acquire an error, gaining or losing a few seconds each day. In this case, its accuracy is reducing over time (e.g. it might be out by a minute or more after a month), but its precision is still very good (day to day readings are consistent within a second or so). However, if after resetting it, the minute and second hands fall off, it would still be very accurate but it would have low precision, as you can only tell the time of day to about plus or minus 10 minutes or so. With a GPSr, if you go back to the same spot (with known true coordinates) many times, and record the displayed coordinates on each occasion, you can get some indication of your unit's accuracy and precision (at least inasmuch as they can be measured at that particular location - accuracy and precision at other locations, or at other times of day, with different reception conditions may be different!) If your coordinates are generally very tightly clustered, this indicates high precision. If they are loosely scattered, this would indicate relatively low precision. If the mean location (the centre of the scattered group) is dead on target, this would indicate high accuracy. If the mean location is biased away from the true location, this indicates relatively lower accuracy. Finally, "EPE" is Garmin's terminology for "Estimate of Position Error". It is no more than an estimate, and it is based upon the instrument's self-diagnosis of the quality of the signal it currently has. It is based upon a proprietary algorithm (Garmin don't state exactly what it is reporting), and it is NOT a guarantee of accuracy or precision. It is generally taken as being the 50% CEP (Circular Error of Probability), meaning that the instrument estimates that you have a roughly 50% chance of being within the displayed EPE of your true location, and a 50% chance of being further away. There is no theoretical upper limit as to how far away you might be at any given time. (I.e. the true error can be much, much higher than the displayed EPE, although most of the time, the displayed EPE is a reasonable estimate of the current probable accuracy and precision.) Unfortunately, seeing the displayed EPE doesn't tell you what the real current error is, it only provides a guide. Hope this helps!

Have a look at the latest version of Google Maps for Windows Mobile devices (may also be available for other platforms like iPhone, Palm, etc). It has an option called "Latitude" to broadcast "My Location", so that you can see your own location, plus locations of your contacts who have the service activated. (Only works in mobile phone range, of course.) Details here: http://www.google.com/mobile/default/latitude.html Hope this helps!

Not based on any real knowledge, but I would hazard a guess that it is writing the two records as two separate actions, using the current GPSr output at two slightly different times (albeit almost the same time), with slightly different coordinates and elevations. I agree that it is unlikely to be that one is using GPS elevation, and the other is using barometric altimeter elevation - you will see variance of a LOT more than a fraction of a foot between these two readings. Hope this helps!

Ouch!

The Red Arrow only appears when you are navigating to a waypoint or following a route or similar. If you are not navigating, you won't see the Red Arrow, only the compass ring. (The Compass Ring shows you which way you are facing or moving. The Red Arrow shows you which way to your next destination.)